After the Kobelco SK330-8 engine started, the exhaust pipe was loud and loud.
Not long ago, a Kobelco 330-8 excavator was successfully repaired in Enshi, Hubei. The symptom was: the exhaust pipe of the SK330-8 engine was larger and accompanied by the abnormal noise after the engine was started.
After the Kobelco SK330-8 engine starts, the exhaust pipe is loud and loud.
First of all, it is found that there is knock on the cylinder of the engine, so is the cylinder knock? Then the data line was detected, and it was found that the fuel injector was indeed defective. After enquiring, the six nozzles were changed just a few days ago, but they seemed to be refurbished. At this point, then dismantle it.
When the valve chamber was removed, it was found that the intake cross of the four cylinder broke apart. It was thought that the cause of the failure was attributed to this, but the leader said to look up the cylinder head to see if there was any problem. Well, after a lot of hard work, the cylinder head was lifted and the piston of the six cylinders was all under the valve. It was very strange that the top was all the intake side, and the cylinder head and the body had not been worn out. But why did the top be the intake side?
There are two possibilities, one is connecting rod tile, the other is two valve train. If the connecting rod bush is worn, it will cause six pistons to move laterally in the same direction when they work, and the possibility of pushing them to the intake valve is less likely. Therefore, the valve checking mechanism is inspected emphatically, and the camshaft is not bent, the rocker shaft and the rocker arms are all normal, so there is no clue to the train of thought. During a half-time break, the camshaft and cam gear seemed to be somewhat offset, and there was a slight smile on the eyebrows. The camshaft and gear are dismantled and found that the steady pin has been misplaced, and the stable pin groove on the camshaft has been deformed.
The root cause of the failure is the shift of the gear, which causes a certain amount of change in the direction of the camshaft and the intake valve, which causes the piston to reach the intake gate when it reaches the top stop.
